US5862789A - Applied ignition internal combustion engine whose pistons have elliptical recesses - Google Patents
Applied ignition internal combustion engine whose pistons have elliptical recesses Download PDFInfo
- Publication number
- US5862789A US5862789A US08/838,829 US83882997A US5862789A US 5862789 A US5862789 A US 5862789A US 83882997 A US83882997 A US 83882997A US 5862789 A US5862789 A US 5862789A
- Authority
- US
- United States
- Prior art keywords
- cylinder
- piston
- ellipses
- recess
- ellipse
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B69/00—Internal-combustion engines convertible into other combustion-engine type, not provided for in F02B11/00; Internal-combustion engines of different types characterised by constructions facilitating use of same main engine-parts in different types
- F02B69/02—Internal-combustion engines convertible into other combustion-engine type, not provided for in F02B11/00; Internal-combustion engines of different types characterised by constructions facilitating use of same main engine-parts in different types for different fuel types, other than engines indifferent to fuel consumed, e.g. convertible from light to heavy fuel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B23/00—Other engines characterised by special shape or construction of combustion chambers to improve operation
- F02B23/08—Other engines characterised by special shape or construction of combustion chambers to improve operation with positive ignition
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B43/00—Engines characterised by operating on gaseous fuels; Plants including such engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B1/00—Engines characterised by fuel-air mixture compression
- F02B1/02—Engines characterised by fuel-air mixture compression with positive ignition
- F02B1/04—Engines characterised by fuel-air mixture compression with positive ignition with fuel-air mixture admission into cylinder
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B2275/00—Other engines, components or details, not provided for in other groups of this subclass
- F02B2275/14—Direct injection into combustion chamber
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/12—Improving ICE efficiencies
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/30—Use of alternative fuels, e.g. biofuels
Definitions
- the present invention relates to the field of applied ignition internal combustion engine. Specifically, the present invention relates to at least one cylinder in which a piston slides along the cylinder axis, with a cylinder head Capping the cylinder and, together with the piston and cylinder, defining a combustion chamber, the piston having a recess open toward the cylinder head.
- Engines of the aforementioned type that operate on a lean mixture are particularly the subject of the invention.
- applied ignition engines operating on a highly dilute mixture considerably reduce pollutant emissions such as nitrogen oxides (NO X ).
- Combustion characteristics depend on geometric factors (shape of chamber, shape of recess in piston, position of spark plug, and position of intake system) and aerodynamic factors (turbulence and speed), distribution factors, etc.
- optimization of the internal aerodynamics proves to be an important step in the design of an applied ignition engine operating on a lean mixture.
- the design of the internal aerodynamics in the chamber at the time of ignition must contribute to increasing combustion rates and favoring stability of the flame upon ignition.
- the flow characteristics at this time in the chamber depend on the result of the interaction between the post-intake aerodynamics and the shape of the combustion chamber.
- the turbulence levels and rates must in particular be optimized to favor ignition stability and flame propagation in the chamber.
- U.S. Pat. No. 5,351,665 describes a combustion chamber formed in the piston by a recess with a particular geometry.
- the present application endeavors to meet the aerodynamic objectives listed above to contribute to optimizing the energy efficiency/emissions compromise.
- the invention optimizes turbulence and speed levels near the spark plug since too high a turbulence level increases cyclic instability.
- Another objective of the invention is to maximize mean turbulence levels in the chamber using in particular the interaction between the chamber shape and swirling around the cylinder axis to generate turbulence.
- the main problem is to prevent excessive gas flowrates at the time of ignition as these rates can affect combustion quality.
- the recess of the piston open toward the cylinder head, has at least one space with an ellipsoid section along a transverse plane of the piston whose main axis and generatrices are essentially parallel to the lengthwise axis of the piston in order to reduce the ratios between area and volume in the combustion chamber and optimize turbulence levels at the end of the compression cycle.
- the ellipses are such that 0 ⁇ 0.6 with ##EQU2## where G R is the major radius of at least one of the spaces and P R is the minor radius of said space or spaces.
- the recess has two spaces having the following characteristics:
- G R is such that: 0.25 ⁇ B ⁇ G R ⁇ 0.40 ⁇ B;
- minor radius P R is such that: 0.10 ⁇ B ⁇ P R ⁇ 0.25 ⁇ B with
- the position of the spaces is such that, with C i being the center of symmetry of each ellipse and D i being the distance between the cylinder axis and the center C i of each ellipse: 0 ⁇ D i ⁇ 0.20 B.
- the angle ( ⁇ ) between the major axes of each ellipse can be 0.
- the angle ( ⁇ ) between the major axes of each ellipse can be substantially equal to 90°.
- the invention relates to the design of an internal combustion engine, whose cylinder head may or may not be flat, that can be used in a lean mixture with natural gas with a better compromise between energy efficiency and pollution emission than current technologies.
- the invention relates to the development of recess geometries in the piston that allow high turbulence levels to be developed at the end of compression.
- These geometries were created from internal aerodynamic analysis and are based on specific elliptical shapes. These shapes contribute to reducing the area/volume ratios in chambers and hence reducing heat transfers while improving energy efficiency.
- these geometries increase turbulence levels at the end of compression by breaking up the flow coming from the intake. This optimizes the combustion characteristics.
- the judicious disposition of the ellipses of which the recess in the piston is made yields the aerodynamics most favorable to realizing our objectives during the compression phase, taking into account constraints linked to manufacture of the parts.
- High-power Diesel engines can be modified according to the invention to operate on natural gas with very low pollution emissions (particularly of NO x and C0 2 ) associated with an efficiency comparable to that of a direct-injection Diesel engine.
- FIG. 1 shows in lengthwise section an internal combustion engine with a chamber according to the invention
- FIG. 2 is a top view of a piston with a recess according to the invention.
- FIG. 3 is a top view and FIG. 3A a cross-section of the piston with a particular recess according to the invention
- FIG. 4 is a top view and FIG. 4A a cross-section of the piston with a recess according to another embodiment of the invention.
- FIG. 5 shows mean turbulent kinetic energy curves as a function of crankshaft angle, obtained for different piston recess geometries.
- FIG. 1 illustrates in lengthwise section the combustion chamber 1 of an applied ignition internal combustion engine according to the invention.
- the combustion chamber is defined by a piston 2 which slides lengthwise in cylinder 3 and by a cylinder head 4 which in the normal fashion has a spark plug 5 and one or more openings (not shown) for intake and exhaust.
- Piston 2 has a recess of a specific shape.
- Recess 6 is open towards cylinder head 4 and is in the form of at least one space with an ellipsoid section containing ellipses along a transverse plane of the piston.
- the main axis of the at least one space is substantially parallel to the lengthwise axis of the cylinder.
- the generatrices of recess 6 are essentially parallel to the lengthwise axis and hence to the walls of the cylinder.
- the ellipses have a flat portion ⁇ such that ##EQU3## where G R is the major radius the ellipses of the at least one space and P R is the minor radius of the ellipses of the at least one space.
- recess 6 has two ellipsoid spaces 61, 62 as shown in FIG. 2.
- the depth P B of each space is greater than 15% of bore B of the cylinder.
- major radius G R of each ellipse is between 0.25 and 0.40 times the bore B of the cylinder: 0.25 B ⁇ G R ⁇ 0.40 B.
- the minor radius P R of each ellipse is preferably between 0.10 and 0.25 times the bore B of the cylinder: 0.10 B ⁇ P R ⁇ 0.25 B.
- the major radius is substantially equal to half the major axis of the ellipse and the minor radius is equal to half the minor axis of the ellipse.
- the centers of symmetry C i of the ellipses are located at a distance from center C of the bore that is less than 0.20 times the value of bore B.
- the angle ⁇ between the major axes of each space can be any angle.
- FIG. 3 shows an embodiment of the invention according to which the major axes of the ellipses are perpendicular to each other.
- bore B of the cylinder in this case is equal to 120 mm
- major radius G R of each space is equal to 40 mm
- minor radius P R is equal to 24 mm.
- Center C 1 is equated with center C of the cylinder while center C 2 of the second space is located at a distance of 5.4 mm from center C.
- FIG. 3A shows more precisely how recess 6 whose generatrices are parallel to the piston axis is designed.
- the cross sections are equal whatever the depth of the recess.
- the base and top of recess 6 has small variations in cross section due to manufacturing constraints.
- FIG. 4 illustrates another embodiment of the invention where recess 6 has two spaces with an ellipsoid cross section, of which the major axes of the ellipses are substantially parallel with each other.
- bore B is equal to 120 mm
- major radius G R of each ellipse is equal to 40 mm
- minor radius P R of each ellipse is equal to 24 mm
- centers of symmetry C 1 and C 2 of each ellipse are each 12 mm from center C of bore B.
- the other details of this geometry can be seen in FIG. 4A and are similar to those provided in relation to FIG. 3A.
- each of centers C1 and C2 is chosen to accentuate the offcentering effect relative to the axis of the combustion chamber while taking certain dimensional constraints into account.
- FIG. 5 illustrates the improvement of the invention in terms of the turbulence created in the combustion chamber.
- Curves I and II represent respectively the mean turbulence kinetic energy (TKE) as a function of crankshaft angle in a chamber according to FIG. 4 and according to FIG. 3.
- the other curves relate to turbulence kinetic energy for recess geometries not according to the invention.
- Curve III is for a cylinder-shaped recess off-center with respect to the spark plug
- Curve IV shows the performance of a cylindrical recess centered around the spark plug
- Curve V illustrates the turbulence created by a frustroconical recess
- Curve VI relates to an essentially spherical recess; it corresponds to a known geometry used in Diesel engines.
- the increase in turbulence levels in the combustion chamber was obtained during the compression phase by "transforming" the vortex flow coming from the intake.
Abstract
Description
Claims (9)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR9512005A FR2739896B1 (en) | 1995-10-11 | 1995-10-11 | CONTROLLED IGNITION INTERNAL COMBUSTION ENGINE WITH IMPROVED COMBUSTION |
CA002202085A CA2202085A1 (en) | 1995-10-11 | 1997-04-07 | Internal combustion engine with controlled ignition and pistons with ellipsoid cavities |
SE9701276A SE9701276L (en) | 1995-10-11 | 1997-04-08 | Combustion engine with controlled ignition and elliptically recessed pistons |
NL1005777A NL1005777C2 (en) | 1995-10-11 | 1997-04-09 | Internal combustion engine with pilot ignition with pistons with elliptical cavities. |
US08/838,829 US5862789A (en) | 1995-10-11 | 1997-04-10 | Applied ignition internal combustion engine whose pistons have elliptical recesses |
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR9512005A FR2739896B1 (en) | 1995-10-11 | 1995-10-11 | CONTROLLED IGNITION INTERNAL COMBUSTION ENGINE WITH IMPROVED COMBUSTION |
CA002202085A CA2202085A1 (en) | 1995-10-11 | 1997-04-07 | Internal combustion engine with controlled ignition and pistons with ellipsoid cavities |
SE9701276A SE9701276L (en) | 1995-10-11 | 1997-04-08 | Combustion engine with controlled ignition and elliptically recessed pistons |
NL1005777A NL1005777C2 (en) | 1995-10-11 | 1997-04-09 | Internal combustion engine with pilot ignition with pistons with elliptical cavities. |
US08/838,829 US5862789A (en) | 1995-10-11 | 1997-04-10 | Applied ignition internal combustion engine whose pistons have elliptical recesses |
Publications (1)
Publication Number | Publication Date |
---|---|
US5862789A true US5862789A (en) | 1999-01-26 |
Family
ID=27508621
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US08/838,829 Expired - Lifetime US5862789A (en) | 1995-10-11 | 1997-04-10 | Applied ignition internal combustion engine whose pistons have elliptical recesses |
Country Status (5)
Country | Link |
---|---|
US (1) | US5862789A (en) |
CA (1) | CA2202085A1 (en) |
FR (1) | FR2739896B1 (en) |
NL (1) | NL1005777C2 (en) |
SE (1) | SE9701276L (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6502540B1 (en) | 1999-01-19 | 2003-01-07 | Alvin J. Smith | Internal combustion engine gas flow control |
US20060124103A1 (en) * | 2003-12-01 | 2006-06-15 | Komatsu Ltd. | Direct injection diesel engine |
US20090173312A1 (en) * | 2008-01-08 | 2009-07-09 | Mazda Motor Corporation | Internal combustion engine |
CN104047756A (en) * | 2014-06-04 | 2014-09-17 | 邓在积 | Positive covariance engine |
WO2018059928A1 (en) | 2016-09-30 | 2018-04-05 | IFP Energies Nouvelles | Controlled-ignition internal combustion engine with pistons comprising a cavity with evolutive elliptical sections |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5316107A (en) * | 1976-07-30 | 1978-02-14 | Hino Motors Ltd | Combustion chamber of diesel engine |
FR2365697A1 (en) * | 1976-09-23 | 1978-04-21 | Lister & Co Ltd R A | IMPROVEMENTS TO PISTONS OF INTERNAL COMBUSTION ENGINES |
GB2084696A (en) * | 1980-09-30 | 1982-04-15 | Alcan Aluminiumwerke | Piston for an internal combustion engine |
GB2106592A (en) * | 1981-09-23 | 1983-04-13 | Porsche Ag | Spark-ignition engine with an eccentric piston combustion chamber |
US5351665A (en) * | 1992-11-26 | 1994-10-04 | Avl Gesellschaft Fur Verbrennungskraftmaschinen Und Mestechnik M.B.H. Prof. Dr.H.C.Hans List | Internal combustion engine |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60125721A (en) * | 1983-12-12 | 1985-07-05 | Yanmar Diesel Engine Co Ltd | Combustion chamber of direct-injection type diesel engine |
JPH03182617A (en) * | 1989-12-11 | 1991-08-08 | Matsuoka Gijutsu Jimusho:Kk | Combustion chamber for direct injection type diesel engine |
-
1995
- 1995-10-11 FR FR9512005A patent/FR2739896B1/en not_active Expired - Lifetime
-
1997
- 1997-04-07 CA CA002202085A patent/CA2202085A1/en not_active Abandoned
- 1997-04-08 SE SE9701276A patent/SE9701276L/en unknown
- 1997-04-09 NL NL1005777A patent/NL1005777C2/en not_active IP Right Cessation
- 1997-04-10 US US08/838,829 patent/US5862789A/en not_active Expired - Lifetime
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5316107A (en) * | 1976-07-30 | 1978-02-14 | Hino Motors Ltd | Combustion chamber of diesel engine |
FR2365697A1 (en) * | 1976-09-23 | 1978-04-21 | Lister & Co Ltd R A | IMPROVEMENTS TO PISTONS OF INTERNAL COMBUSTION ENGINES |
GB2084696A (en) * | 1980-09-30 | 1982-04-15 | Alcan Aluminiumwerke | Piston for an internal combustion engine |
GB2106592A (en) * | 1981-09-23 | 1983-04-13 | Porsche Ag | Spark-ignition engine with an eccentric piston combustion chamber |
US5351665A (en) * | 1992-11-26 | 1994-10-04 | Avl Gesellschaft Fur Verbrennungskraftmaschinen Und Mestechnik M.B.H. Prof. Dr.H.C.Hans List | Internal combustion engine |
Non-Patent Citations (4)
Title |
---|
Patent Abstract Of Japan, vol. 015, No. 432 (M 1175), Nov. 5, 1991. * |
Patent Abstract Of Japan, vol. 015, No. 432 (M-1175), Nov. 5, 1991. |
Patent Abstracts Of Japan, vol. 009, No. 282 (M 428), Nov. 9, 1985. * |
Patent Abstracts Of Japan, vol. 009, No. 282 (M-428), Nov. 9, 1985. |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6502540B1 (en) | 1999-01-19 | 2003-01-07 | Alvin J. Smith | Internal combustion engine gas flow control |
US20060124103A1 (en) * | 2003-12-01 | 2006-06-15 | Komatsu Ltd. | Direct injection diesel engine |
US7156069B2 (en) * | 2003-12-01 | 2007-01-02 | Komatsu Ltd. | Direct injection diesel engine |
US20090173312A1 (en) * | 2008-01-08 | 2009-07-09 | Mazda Motor Corporation | Internal combustion engine |
US7650872B2 (en) * | 2008-01-08 | 2010-01-26 | Mazda Motor Corporation | Internal combustion engine |
CN104047756A (en) * | 2014-06-04 | 2014-09-17 | 邓在积 | Positive covariance engine |
WO2018059928A1 (en) | 2016-09-30 | 2018-04-05 | IFP Energies Nouvelles | Controlled-ignition internal combustion engine with pistons comprising a cavity with evolutive elliptical sections |
Also Published As
Publication number | Publication date |
---|---|
SE9701276D0 (en) | 1997-04-08 |
FR2739896A1 (en) | 1997-04-18 |
NL1005777C2 (en) | 1998-10-12 |
FR2739896B1 (en) | 1997-12-12 |
SE506730C2 (en) | 1998-02-02 |
CA2202085A1 (en) | 1998-10-07 |
SE9701276L (en) | 1998-02-02 |
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Owner name: INSTITUT FRANCAIS DU PETROLE, FRANCE Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:CHAOUCHE, ALI;HENRIOT, STEPHANE;MONNIER, GAETAN;REEL/FRAME:009002/0770 Effective date: 19970926 |
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